PHILIPPINE health authorities have identified at least 44 people who had close contact with a Finnish visitor who tested positive for an Omicron mutation of the coronavirus.

Among them were 30 co-passengers on her flight to the Philippines, Health Undersecretary Maria Rosario Vergeire told the ABS-CBN News Channel on Thursday. All of them were being monitored for the BA.2.12 Omicron subvariant, while some have tested negative.

The Department of Health (DoH) on Wednesday said the Finnish woman, 52, experienced mild symptoms nine days after arriving on April 2. She had not been isolated because she was fully vaccinated and did not show symptoms when she arrived.

The woman traveled to a university in Quezon City and to Baguio City to conduct seminars before recovering and returning to Finland on April 21.

The US Center for Disease Control (CDC) has flagged the sublineage of the Omicron variant, which has been detected in a growing number of patients in the US.

“Most of them were fully vaccinated,” Ms. Vergeire said of the close contacts. “Some were tested and were negative. Nobody is experiencing symptoms as of this time.”

The BA.2.12 Omicron subvariant makes up majority of coronavirus cases in the US, DoH said, citing data from the CDC.

DoH noted that of 132 local samples recently sequenced, 63% or 83 were Omicron. The samples came from 10 regions and the Finnish who tested positive for the BA.2.12 subvariant.

The woman could either have been infected on her way to the Philippines or when she arrived, Ms. Vergeire said.

“There’s 14-day incubation of the virus. She might have gotten that during her travel. She arrived here on April 2, she had symptoms on April 10, the ninth day of her infection,” she added.

Meanwhile, Party-list Rep. Angelica Natasha Co urged the government to set higher requirements for vaccinations. 

“The DoH and Inter-Agency Task Force should raise the minimum for fully vaccinated status to having the booster shot, not just the primary dosage,” she said in a statement. “By the end of July or three months from now, the definition of fully vaccinated status should be adjusted to having the second booster shot.” 

Second booster shots should be made available to everyone to swiftly respond to the risk of another surge, Ms. Co said.

More than 67 million Filipinos have been fully vaccinated against the coronavirus, about 13 million of whom had also been injected with booster shots, according to DoH.

The Philippines might experience another surge in coronavirus infections by May or June, similar to what other countries are experiencing now, OCTA Research Group fellow Fredegusto P. David told a virtual town meeting on Monday. 

The Philippines on Monday started giving out second booster shots against the coronavirus to seriously ill people.

Among those eligible for the shots are people with weak immune systems, those living with HIV, cancer, transplant and bedridden patients, and the terminally ill, the Department of Health (DoH) said in a statement.

A COVID-19 outbreak could happen among unvaccinated Filipinos, said Teodoro J. Herbosa, an adviser at the National Task Force Against COVID-19.

OCTA President Ranjit S. Rye, citing a poll they conducted on March 5 to 10, said 77% of Filipinos were willing to get their booster shots, while 23% were unsure. 

He added that 53% of those who were unsure felt that booster shots are safe, while 35% thought these are not needed.

Only certain areas in the capital region were ready to roll out the second booster shots, the Health department said on Monday. 

Members of the vulnerable sector should get a vaccine brand that is different from their earlier shots for more protection, according to Nina Gloriani, who heads the government’s vaccine expert panel.

The second booster vaccine should be injected three months after the first, the Health department said earlier.

The government would soon give out a second booster for seniors and health workers to boost protection, said Ms. Gloriani, who heads the government’s Vaccine Expert Panel.

An independent advisory body of DoH would probably release its recommendations on the use of second booster shots for these categories this week.

Ms. Gloriani said they don’t expect any problems about safety.

Some medical frontliners and senior citizens this week wrongly received second booster shots at a hospital in Metro Manila even if the initial rollout was supposed to be limited to people with a weak immune system. — Norman P. Aquino and Alyssa Nicole O. Tan